How does KAYAK find such low prices on flights from Ontario to Seattle?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Seattle. Visit our flight page for the latest deals!>/a>

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Seattle?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Ontario is likely to change within 7 days, so travelers know whether to wait or book now. Visit our flight page for the latest deals!>/a>

What is the Hacker Fare option on flights from Ontario to Seattle?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Ontario with another airline. Visit our flight page for the latest deals!>/a>

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Seattle?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best. Visit our flight page for the latest deals!>/a>

$103 CHEAP FLIGHTS from Ontario to Seattle

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

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Cheap Flights from Ontario to Seattle

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Ontario to Seattle

Thu, Sep 4 - Sat, Sep 13

6:00 am - 12:59 pmYKF-SEA

9h 59m1 stop

1:50 pm - 12:45 amSEA-YKF

7h 55m1 stop

$185WestJet

Find Deal

Wed, Oct 15 - Thu, Oct 23

6:00 am - 12:59 pmYKF-SEA

9h 59m1 stop

7:05 am - 6:55 pmSEA-YKF

8h 50m1 stop

$186WestJet

Find Deal

Wed, Aug 20 - Wed, Sep 17

6:00 am - 12:58 pmYKF-SEA

9h 58m1 stop

1:50 pm - 12:45 amSEA-YKF

7h 55m1 stop

$190WestJet

Find Deal

Wed, Oct 8 - Wed, Oct 15

4:45 pm - 7:04 pmYYZ-SEA

5h 19mnonstop

7:18 am - 3:00 pmSEA-YYZ

4h 42mnonstop

$227Alaska Airlines

Find Deal

Fri, Nov 7 - Sun, Nov 16

7:30 pm - 9:56 pmYYZ-SEA

5h 26mnonstop

8:00 pm - 6:29 amSEA-YYZ

7h 29m1 stop

$231Air Canada

Find Deal

Wed, Sep 17 - Tue, Sep 23

12:25 pm - 7:31 pmYTZ-SEA

10h 06m1 stop

7:15 am - 7:49 pmSEA-YTZ

9h 34m1 stop

$246Air Canada

Find Deal

Wed, Sep 3 - Thu, Sep 4

6:20 pm - 10:59 pmYYZ-SEA

7h 39m1 stop

10:00 am - 12:50 amSEA-YYZ

11h 50m2 stops

$252United Airlines

Find Deal

Thu, Aug 14 - Thu, Aug 21

9:55 am - 8:41 pmYXU-SEA

13h 46m2 stops

7:35 pm - 5:14 amSEA-YXU

6h 39m1 stop

$252

Find Deal

Wed, Sep 3 - Sat, Sep 6

7:00 am - 10:59 pmYYZ-SEA

18h 59m3 stops

7:15 am - 6:34 pmSEA-YYZ

8h 19m1 stop

$258

Find Deal

Thu, Aug 14 - Thu, Aug 21

6:15 am - 11:00 amYXU-SEA

7h 45m1 stop

10:55 pm - 5:07 pmSEA-YXU

15h 12m2 stops

$385United Airlines

Find Deal

Useful Info

Low season	January
High season	August

Best time to beat the crowds with an average 14% drop in price.

Most popular time to fly and prices are also 4% lower on average.

How does KAYAK find such low prices on flights from Ontario to Seattle?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Seattle.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Seattle?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Ontario to Seattle?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Ontario with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Seattle?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to Seattle

Airports

Cabin class

Complete your trip

Direct Flights

Flights to other cities

Origins

Other airports

Return flight deals

Information on the airport you'll fly into in Seattle

Seattle (SEA)

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.

$103 Find Cheap Flights from Ontario to Seattle

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

Cheap Flights from Ontario to Seattle

Recent round-trip flight deals from Ontario to Seattle

Recent one-way flight deals from Ontario to Seattle

Recent last minute flight deals from Ontario to Seattle

Recent direct flight deals from Ontario to Seattle

Good to know

FAQs for booking flights from Ontario to Seattle

How does KAYAK find such low prices on flights from Ontario to Seattle?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Seattle.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Seattle?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Ontario to Seattle?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Ontario with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Seattle?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to Seattle

Information on the airport you'll fly into in Seattle

Cabin class types available on flights to Ontario

Complete your trip to Seattle with a hotel stay or car rental

Find direct flights for Seattle

Flights to other popular destinations

Flights from domestic origins to Seattle

Choose which airport to fly into in Seattle

Find deals for your return flight